Overview

Override motion refers to changing the parameters of a motion command before the motion command finishes. Any parameter of the motion command may be changed, including the target position.

Override motion can be executed in one of two ways:

Executing the same type of motion command with a different set of parameters.

The following functions support override motion in this manner:

Function	Remarks
StartPos, StartMov	Both of these functions can be overridden by a StartPos or StartMov command.
StartLinearIntplPos, StartLinearIntplMov, StartCircularIntplPos, StartCircularIntplMov	All of these functions can be overridden by a StartLinearIntplPos, StartLinearIntplMov, StartCircularIntplPos, or StartCircularIntplMov command.
StartVel	This function can be overridden by a StartVel command.
Other Functions	Several other functions exhibit characteristics similar to override motion. For example, calling the Pause function on an axis, and then calling Resume before the axis fully stops will override the pause command with a resume command. Similarly, calling the Stop function will override the current motion of the axis with a stop motion.

Executing a override function.

The following are override functions that override the current motion command executed by the axis. See the description for each function for information regarding which motion commands can be overridden with that function.

• OverridePos

• OverrideMov

• OverrideVel

• OverrideAcc

• OverrideDec

• OverrideJerkAcc

• OverrideJerkDec

• OverrideProfile

• OverridePathIntplVelocityMultiplier

• OverridePathIntpl3DVelocityMultiplier

If the API Wait Until Motion Start parameter is disabled (it is enabled by default), override motion cannot be executed until one or more communication cycle elapses after the motion function is called.

During an override, the axis starts the execution of the new command while keeping the current velocity (and for certain profile types, keeping the current acceleration as well). If the starting velocity of the override command is set to 0, the override command will start from the current velocity. If the starting velocity of the override command is not set to 0, the override command will start from the specified starting velocity (see startingVelocity).

The following plots show the position, velocity, and acceleration of an example override motion command.